[PATCH v3 00/15] drm+msm: Shrinker and LRU rework

From: Rob Clark
Date: Tue Jul 26 2022 - 13:50:22 EST


From: Rob Clark <robdclark@xxxxxxxxxxxx>

Mostly a resend with switch to lockdep asserts for the GEM LRU helper
and conversion of msm locking checks to lockdep asserts, since that
seemed like a good idea.

original description below:

This is mostly motivated by getting drm/msm to pass an i-g-t shrinker
test that I've been working on. In particular the test creates and
cycles between more GEM buffers than what will fit in RAM to force
eviction and re-pin. (There are sub-tests that cover this case both
single threaded and with many child processes in parallel.)

Getting this test to pass necessitated a few improvements:

1. Re-ordering submit path to get rid of __GFP_NORETRY (in the common
case, doing this for syncobjs is still TODO)
2. Decoupling locks needed in the retire path from locks that could
be held while hitting reclaim in the submit path
3. If necessary, allow stalling on active BOs for reclaim.

The latter point is because we pin objects in the synchronous part of
the submit path (before queuing on the drm gpu-scheduler), which means
in the parallel variant of the i-g-t test, we need to be able to block
in the reclaim path until some queued work has completed/retired.

In the process of re-working how drm/msm tracks buffer state in it's
various LRU lists, I refactored out a drm_gem_lru helper which, in
theory, should be usable by other drivers and drm shmem helpers for
implementing LRU tracking and shrinker.


v2: rebase + small fix in 13/13
v3: use lockdep_assert_held in GEM LRU helper, and add a couple patches
at the end to convert MSM from WARN_ON(!is_locked()) to lockdep
asserts

Rob Clark (15):
drm/msm: Reorder lock vs submit alloc
drm/msm: Small submit cleanup
drm/msm: Split out idr_lock
drm/msm/gem: Check for active in shrinker path
drm/msm/gem: Rename update_inactive
drm/msm/gem: Rename to pin/unpin_pages
drm/msm/gem: Consolidate pin/unpin paths
drm/msm/gem: Remove active refcnt
drm/gem: Add LRU/shrinker helper
drm/msm/gem: Convert to using drm_gem_lru
drm/msm/gem: Unpin buffers earlier
drm/msm/gem: Consolidate shrinker trace
drm/msm/gem: Evict active GEM objects when necessary
drm/msm/gem: Add msm_gem_assert_locked()
drm/msm/gem: Convert to lockdep assert

drivers/gpu/drm/drm_gem.c | 183 +++++++++++++++++++++++++
drivers/gpu/drm/msm/msm_drv.c | 18 ++-
drivers/gpu/drm/msm/msm_drv.h | 70 +++++++---
drivers/gpu/drm/msm/msm_gem.c | 179 +++++++++---------------
drivers/gpu/drm/msm/msm_gem.h | 123 ++---------------
drivers/gpu/drm/msm/msm_gem_prime.c | 4 +-
drivers/gpu/drm/msm/msm_gem_shrinker.c | 164 ++++++++++------------
drivers/gpu/drm/msm/msm_gem_submit.c | 78 ++++-------
drivers/gpu/drm/msm/msm_gpu.c | 3 -
drivers/gpu/drm/msm/msm_gpu.h | 10 +-
drivers/gpu/drm/msm/msm_gpu_trace.h | 36 +++--
drivers/gpu/drm/msm/msm_submitqueue.c | 1 +
include/drm/drm_gem.h | 56 ++++++++
13 files changed, 505 insertions(+), 420 deletions(-)

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2.36.1